Gear-wheel



v material used at this place `ao tion of the wheel.

lferent from that UNITEDSTATES .PATENT OFFICE.

:DAVID EITZPATEICK, or CLEVELAND, omo, AssIGNoR To THE CLEVELAND WORM a GEAR COMPANY, or CLEVELAND, omo. f

GEAR-WHEEL.

Application filed February To aZZ 'zu/tom t may concern.'

Be it known that I, DAVID FITZPATRICK, a subject of the King of Great Britain, and resident of Cleveland, county of Cuyahoga, and State of Ohio, have invented certain new and useful Improvements ,in Gear- VYheels, of which the following' is a specification.

lily invention relates in general to a wheel having a periphery formed of material difand specifically relates tol a gear wheel, the toothed portion of which is `of different material from the central portion. Y

`The primary object of the invention is to provide a simple and inexpensive type of wheel designed so that the parts which constitute the working faces or the parts which are subjected to the greatest strains during use, may bemade of a material best suited for the work required of this part and the other structural parts made of relatively cheaper material or of material best suited for the work required of these other parts.

Incidental tok this general object, it is further desired, to form the working surfaces of the least possible amount of the and further to provide a constructionby which this relatively small amount of material is securely and permanently fastened to the body por- Still further objects of the invention, when considered in connection with a gear wheel, are to provide the toothed portion of the least possible amount of material, to

reinforce this portion against distorting strains in all directions and to provide an anti-creeping connection between each tooth and the body portion of the gear wheel.

Various other objects and advantages of the invention will be in `part obvious from an inspection of the accompanying drawings and in part will be more fully set forth in the following andthe inventionV also consists in certain new and novel features of construction `and combination offparts hereinafter set forth and claimed.

Specification of Letters Patent.

of the body of the wheel particular description of one v form of ydevice embodying my invention, cross-section and Patented Nov'. 9, 1920.

10, 1916. Serial No. 77,361.

In the accompanying drawings:

Figure l is a sectional view taken through the medial plane of the upper half of a gear wheel constituting a preferred embodiment of my invention; and

Figs. 2 and 3 arek each transverse sectional views taken respectively on the lines 2-2 and 3-3 of Fig. l.

The form of wheel illustrated isa spiral gear wheel particularly designed to mesh with a worm to constitute part of a driving connection in an automobile power plant.

The wheel includes a `central portion or inner band a formedof sometough and preferably cheapmetal such as cast-iron and a peripheral or outer band of a bronzemetal. The central portion comprises a rim Glhaving inwardly projecting andperforated lugs 7 spaced about the inner periphery and deooncaved transversely of the wheel.

Circumferentially this outer periphery is provided with spaced apart wide flat projections l0 forming similarly shaped recesses l1 therebetween.V These parts are sodesigned that the tops of the projections and the bottom faces of the recesses are flat, with the flat portions` longer, `circumferentially of the wheel, than the fiat tops of the projections similarly measured.`

The central portion` of the wheel is provided with a plurality of locking channels l2 forming by-passes spaced circumferentially, curved from one to another point in the groove 9 and with the curved or crotch portionrcontained"largely in the rim portion of the wheel. l J

The central portion of each projection l0 is recessed to provide acentrally disposed locking notch 13, parabolical in transverse extending substantially to thebottom of theprojection.

The outer band 5 is cast in the form of a corrugated bandpthe outwardly extending projections of whichconstitute gear teeth 14,

of the recesses Vslightly of the outer rim cast .material with the major any bending action is terial. V

Alocking loop 15 of metal integral With the outer band and'extending frointlie inner face of one to another of the inwardly extending projections Zfitting in the recesses 11 is positioned channels 12.

The Wheel is constructed preferably by formed interiorly of another grade or macasting the inner band inthe form described Whch is then placed iii a niold andthe metal about the inner band in a' manner so that the metal runs through the several passagewaysV or channels l2 to form the locking loops. Y Y l By meansof av device of this character, a

construction is provided in which the'bands are securely locked against displacement in anydirection. Transverse movement is resisted at the base lof the outer band due to the concave fit between the bands and at the tops of the projections Vdue to the interlityting tongue and at the center of each projection. Any tendency tocreep circumferentially` is Vresisted by the tongue and groove construction formed by the-lateral projectionson the inner band extending intothe similarrecesses formed thereby in the outerl band, and as these tongues are of some material thickness eliminated.

As a further precaution against relative movement the loclringloops are utilized, thus v securely binding the bands together and forming, in effect, a one-piece vconstruction with all the advantages of an integral casti ing.

By means .o

this lconstruction there is provided an economical"distribution of the r more expensive bronze.'V

teeth have a material .thickness of this metal, Where necessary, but the thick baseportion oi' each tooth has an iron projecting into the bottom thereof.

rthisY insures asaving ofbronze metal at a,V

place Where solidbronze is not only unnecessary but the backing'of'iron adds a tensile f strength to the teeth not possible Where they arey constructed entirely of Vbronze metal. i he bronze metal is extended forsome material depth at the medial-planeof therim outer periphery of the cen-V lO extend centrally into portion of its base y'cess being positioned Within the part Within each of the locking f projections r lgroove connection termed:

lentially of each othein integral extension All ofY the geari insert of the cheaper (see Fig. 2) thus distributing the metal Where it is most likely to be needed as the gear teeth Wear awa-y and insuring a maximum life to the Wheel.

HavingV thus described my invention, l claim :l

1. A gear Wheel including a center portion provided with cii'cumi'erentially spaced projections extending radially therefrom, a toothed metallic band encircliiigsaid center portion and provided with a recess designed to containV one of said projections thereby to assist in retaining the rim in place, said reoi the band forming one of the teeth thereby economizing in the use ot metal constituting the rim.

2. A metallic band VVdesigned to constitute the tooth'edportion -o a gear Wheel, the inner periphery of said band being corrugated transversely oit the plane of the rim and having a. radial thickness of said metal deepest at center and decreasing in depth toward each side, the corrugations at the outer peripheryconstituting gear teeth and a central reinforcing portion disposed Within said band and fastenedl thereto.

3. A' gear Wheel including a pair of concentrically disposed rims, the outer rim provided with gear teeth andalso provided with fitting. into the inner rim to prevent relative movement betiveenthe rims,

said projections being spaced apartv circum- Perentially or" the Wheel a distance-substanially equal to the similar Width of the proections. 1

4t. A-,device oit the class described,"com prising a pair ofrims iitting one Within the other, ivith'the engaging surfaces of said rims -concaved `laterally of the plane of the device' and extending `from side to sideV and said engaging surfaces Vbeing corrugated,

Vvvith the y corrugations positioned relatively vclose together, thereby to assist in preventing relative movement of the rims circumfer- 5. 1n a device of the class described, the combination of tivo rims, one fitting Within the other, one ofthe rims provided withan looped through the other rim to retain the rims in place.

5.6.v In a device ot the class described, the combination of tivo interittin'g rimshaving a-common contacting surface, thebuter of said rims `having an integralextension passingy across said-surface and through the innerrini. .y

7. ln a device of the class described, the

Vcombination of" tvvo' interfitting frims,` the outerrimprovided with a Curved extension cast into. the'otherrim to fasten the rims together against' relative-'movement in all Vdirections.

8. A Wheel comprising an inner member provided with a curved into the periphery thereof, an outer band periphery of the inner member and having a portion projecting into said curved passageway.

9. A gear Wheel including an inner member and a toothed member cast about the periphery of the inner member, each tooth of said tooth forming member having a tongue and groove connection with the inner member.

10. A gear Wheel including an inner member and a toothed member cast about the periphery of the inner member, each tooth of said tooth forming member having a tongue and groove connection with the inner member, certain of the tongues of said connecions being united through the inner meml1. A gear having a center of comparatively strong metal and a surrounding ring of comparativel f Weak anti-friction material, said parts cast together` and having inter-engaging shoulders adapted to restrain relative movement in opposite axial directions and an extension having opposite ends formed integrally with said, surrounding ring and passing through an adjacent part of the center.

12. A gear having a center of comparatively strong Vmetal and teeth of comparatively Weak anti-friction material, and stubs formed in the'center and entering said teeth.

13. A gear having a center of comparatively strong metal with an annular groove in its outer face, and a ring of comparatively Weak anti-friction material cast in said groove, said center having also openings extending toward the axis and said ring having projections cast therewith and entering said openings.

14. A gear having a center of cast iron with an annular groove extending around the rim thereof and With holes in said rim and a bronze ring cast in said groove and with projections entering the holes in the rim of the cast iron center, so as to firmly anchor the bronze ring on the cast iron center said rim having teeth cut therein.

igned at Cleveland, in the county of Cuyahoga, and State of Ohio this 4th day of February, 1916.

DAVID FITZPATRICK. 

